this is my first c3 and I need to find a diagram to figure out my headlight problem or some leads on what to look for on what might be wrong

 

Try this link, it might help. It is very descriptive of how these things work.
http://vetteworks.tripod.com/techdocuments/Vaccum.html

 

Let me know how things go. I'm going to be tackling this on my 77 in a few weeks, once I'm done cleaning up my engine and compartment.

Did they both get stuck up at the same time?


[Modified by noblejr, 10:07 PM 4/11/2004]

 

well I got the car last week and I have been cleaning on it all week (amazing how some people would treat a car like this) and when I got the car both headlights were stuck up

 

I can tell you the process I will go through when I start troubleshooting my headlight problem in my 77. Since I don't know how much you know, I'll try to cover everything. It's raining right now but tommorow I'll go look under the cover and see if I've forgotten anything.

First, only one headlight stays up. This makes things a bit easier in that anything controling both headlights won't be at fault.

I have to get a vacuum gauge. I'm planning on getting something nice, maybe digital, since I'm positive I'll be using it again frequently. Then I'm going to start checking lines. There are 2 lines in the actuator; one for up and one for down. I'll check the down line. If the down hose has a good vacuum then my actuator is having problems. If it does not have a vacuum, it's time to start backtracking through the system to find out why. The up and down hoses connect the actuator to a relay. This vacuum relay switches the up or down hoses to the vacuum reservoir, the large tube behind the bumper that holds a vacuum so you can raise or lower the headlights after the engine has turned off. The first thing I want to know about the relay is if there is a vacuum at it. I'll test the reservoir hose first. Then I'll check the hoses coming in all the way from the firewall. If these have a vacuum then the relay switch is bad. If the reservoir has no vacuum I will need to check the hose coming into it. If that has no vacuum then I need to find out where it gets it vacuum. As of right now I do not know where exactly this hose goes to. If the hoses coming from the firewall have no vacuum then I need to go check my switches inside the car, but since only one headlight has a problem, it's most likely either the actuator or the relay and I've found it and fixed it by now. If both headlights are having a problem, I wouldn't start at the actuators but at the relays and branch off from there. I'm not sure how the headlight switch and the override switch are connected but I've got a reference around here somewhere that i'll try to find.

Hope this helps -Jimmy





[Modified by noblejr, 1:52 AM 4/13/2004]